1. Field
This invention relates to apparatus for removing substances, animal life, or materials which are floating at or near the surface of a body of water. More specifically, this invention is directed to an apparatus for use in harvesting brine shrimp.
2State of the Art
Brine shrimp of the genus Artemia, and specifically of the species Artemia salina, are primitive crustaceans which normally live in bodies of water having a high saline content. Most notably, this form of marine life is found in the Great Salt Lake in Utah and similar lakes and ponds throughout the world.
For many years it has been recognized that the eggs of these crustaceans are capable of withstanding drying conditions for long periods of time. In fact, it has been found that eggs removed from water for over three years will hatch upon their being returned to water. This capacity has led to significant commercial interest in harvesting brine shrimp eggs and thereafter using them either for food for aquarium fish or for use in commercial fish farm operations.
Brine shrimp together with their eggs, which will jointly be referred to hereinafter as "brine shrimp," are usually found in colonies or communities which form floating masses on the surface of bodies of water. In order to make harvesting of the shrimp cost beneficial, it is necessary to concentrate a large number of individual brine shrimp colonies into a single large colony or mass.
Brine shrimp eggs are of sufficient size that they are retrievable from the water by use of nets or similar apparatus. The conventional approach in brine shrimp harvesting has involved the placement of one or more fences in the water adjacent to the shore of a body of water. The fences form a boundary or barrier for the shrimp and thus function to trap or direct the shrimp as the tide or wind causes the shrimp colonies to be pushed toward shore. The fences tend to concentrate the smaller shrimp colonies into a sufficiently large and concentrated mass so as to permit cost-effective harvesting. As the shrimp colonies are driven to the shore, the harvesters, using hand-held nets or shovels, scoop the shrimp from the water or the shore and place the shrimp into storage containers.
Observably, the conventional approach is far from effective. The harvester is at the whim of the wind and the tide as far as bringing the shrimp to the harvesting site. Recognizing that the wind or tide could bring the shrimp colony ashore at any of a number of locations, the harvester's success is often dependent on factors outside of his personal control. To improve the effectiveness of this harvesting approach, extensive fencing structures, positioned to extend outward from the shore, and operate to direct incoming shrimp colonies to preselected harvesting sites have been constructed. Understandably, these structures are exceedingly expensive.
Another problem in the conventional approach is the requirement that the harvester have access to extensive areas of shoreline. In order to construct the fencing structures, one must either lease or own large areas of shoreline. This makes harvesting not only expensive, but further, may make harvesting impossible, if shoreline landowners are unwilling to lease or sell their property.
There exists a need for a means and method for harvesting brine shrimp which eliminates the need for expensive shoreline fencing and which further permits the harvester to take advantage of the large shrimp communities which are found naturally off shore.